با سلام دوستان

من برای کش کردن اطلاعات ارسالی از سرور خط به خط با استاد پیش رفتم اما در کمال تعجب برنامم کرش میکنه و ارور کرش هم اصلا نگفته که اشکال در چه کلاسی هست و تنها تفاوتش اینه که استاد در اکتیویتی پیاده سازی میکنه و من در فرگمنت

ممنون میشم کمکم کنید(:

Dao :

@Dao
public interface DataDao {
    @Insert(onConflict = OnConflictStrategy.REPLACE)
    void insert(DataModel dataModel);
    @Query("SELECT * FROM tbl_catch")
    LiveData<List<DataModel>> getListCatch();
}

 : DataBase

@Database(entities = {DataModel.class},version = 1)
public abstract class DataBase extends RoomDatabase {
    static DataBase dataBase;
    public static DataBase getDataBase(Context context){
        if (dataBase==null){
            dataBase=Room.databaseBuilder(context.getApplicationContext(),DataBase.class,"db")
                    .fallbackToDestructiveMigration()
                    .build();
        }
        return dataBase;
    }
    public abstract DataDao getDao();
}

  : Repository

public class Repository {
    private static UrlRetrofit urlRetrofit;
    DataDao dao;
    public Repository(UrlRetrofit urlRetrofit, DataDao dao) {
        this.urlRetrofit = urlRetrofit;
        this.dao = dao;
    }
    public Completable refreshInfo(){
        return urlRetrofit.latest().doOnSuccess(list -> dao.insert((DataModel) list)).ignoreElement();
    }
    public LiveData<List<DataModel>> getListCatch(){
        return dao.getListCatch();
    }
}

: ApiServise

public interface ApiServise {
    @GET("getnews.php")
    Single<List<DataModel>> latest();
}

: ApiServiceProvider

public class ApiServiceProvider {
    public static ApiServise urlRetrofit;
    private static String url="http://192.168.1.108/news/";
    public static ApiServise getUrlRetrofit(){
        if (urlRetrofit==null){
            Retrofit retrofit=new Retrofit.Builder()
                    .baseUrl(url)
                    .addConverterFactory(GsonConverterFactory.create())
                    .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                    .build();
            urlRetrofit=retrofit.create(ApiServise.class);
        }
        return urlRetrofit;
    }
}

: MainViewModel

public class MainViewModel extends ViewModel {
    Repository repository;
    Disposable disposable;
    public MainViewModel(Repository repository) {
        this.repository = repository;
        repository.refreshInfo()
                .subscribeOn(Schedulers.io())
                .subscribe(new CompletableObserver() {
                    @Override
                    public void onSubscribe(@NonNull Disposable d) {
                        disposable=d;
                    }
                    @Override
                    public void onComplete() {
                    }
                    @Override
                    public void onError(@NonNull Throwable e) {
                    }
                });
    }
    public LiveData<List<DataModel>> getLatestsModels(){
        return repository.getListCatch();
    }
    @Override
    protected void onCleared() {
        disposable.dispose();
        super.onCleared();
    }
}

 : ViewModelFactory

public class ViewModelFactory implements ViewModelProvider.Factory{
    Repository repository;
    public ViewModelFactory(Repository repository) {
        this.repository = repository;
    }
    @NonNull
    @Override
    public <T extends ViewModel> T create(@NonNull Class<T> modelClass) {
        return (T) new MainViewModel(repository);
    }
}

: Fragment

public class LastNews extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        return inflater.inflate(R.layout.last_news, container, false);
    }
    MainViewModel viewModel;
    Adapter adapter;
    RecyclerView recyclerView;
    List<DataModel> latestsModels=new ArrayList<>();
    @SuppressLint("FragmentLiveDataObserve")
    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        super.onViewCreated(view, savedInstanceState);
        recyclerView=view.findViewById(R.id.recy_last_news);
        viewModel=new ViewModelProvider(this,new ViewModelFactory(new Repository(ApiServiceProvider.getUrlRetrofit(),DataBase.getDataBase(getContext()).getDao())))
                .get(MainViewModel.class);
        viewModel.getLatestsModels().observe(this, new Observer<List<DataModel>>() {
            @Override
            public void onChanged(List<DataModel> list) {
                recyclerView.setLayoutManager(new LinearLayoutManager(getContext(),RecyclerView.VERTICAL,false));
                adapter=new Adapter(getContext(),latestsModels);
                recyclerView.setAdapter(adapter);
            }
        });
    }
}